Apparatus for opening box blanks



1962 R. A. PEARSON ETAL 3,062,106

APPARATUS FOR OPENING Box BLANKS Filed Aug. 8, 1960 5 Sheets-Sheet 1 Fig. l

INVENTORS. flfmz/zofd a PM YE 1 Nov. 6, 1962 R. A. PEARSON ETAL 0 APPARATUS FOR OPENING BOX BLANKS Filed Aug. 8, 1960 55 Sheets-Sheet 2 Fig. 3

, 43 LE 48 40 3a I] ll ll lLll 1962 R. A. PEARSON ETAL 3,

APPARATUS FOR OPENING BOX BLANKS Filed Aug. 8, 1960 s Sheets-Sheet a United States Patent i 3,062,106 APPARATUS FOR OPENING BOX BLANKS Reinhold A. Pearson and Benny Weremiczyk, Spokane, Wash, assignors to R. A. Pearson Co., Spokane, Wash, a corporation of Washington Filed Aug. 8, 1960, Ser. No. 48,235

1 Claim. (CI. 93-53) This invention relates to an apparatus for expanding and opening box blanks in a box setting-up machine.

Box setting-up machines areemployed in industry to automatically open box blanks of corrugated or other foldable material, and fold the box flaps preparatory to the sealing operations. A problem encountered is the tendency of the opened box to retain its folded shape. This is evidenced by the appearance of a parallelogram cross-section instead of the desired rectangular shape. Often, where high speed loading machinery is used, this tendency of the cartons to collapse causes binding during loading operations and results in lost time and goods.

- It is an object of this invention to provide an apparatus to expand the box blanks initially so as to offset the tendency of the box to resume its collapsed position.

It is another object of this invention to provide such an apparatus which can easily be adapted to prior machines.

Another object is to provide a positive mechanical apparatus to carry out the above steps in timed relation to other box setting-up operations.

These and still further objects will be evident from a study of the following description of one embodiment of the apparatus and method. The accompanying drawings. illustrate the invention as applied to on existing machine. The invention is not intended to be limited by this exemplary disclosure, except as it is defined by the annexed claims.

In the drawings:

FIGURE 1 is an oversall side view of a box setting-up machine with the blank opening apparatus embodied in this invention.

FIGURE 2 is a fragmentary top view showing the box opening mechanism illustrated in FIGURE 1;

FIGURE 3 is an enlarged end view of the blank opening apparatus as seen from the left hand end of FIG- URE 1;

FIGURE 4 is an enlarged sectional view taken along line 44 in FIGURE 3;

FIGURE 5 is an enlarged fragmentary side view showing a first position of the blank opening apparatus; and

FIGURE 6 is similar to FIGURE 5, but shows a second position of the apparatus.

This invention is designed for use on box setting-up machines of the type disclosed in our prior Patent, No. 2,827,338, issued on March 25, 1958, for Box Setting-Up Machine. The general scheme of this machine is the provision of an apparatus to individually feed collapsed box blanks from a stack to an operating position, a box opening apparatus to expand the blank vertically, flap closing mechanisms to bend the box flaps at one end, and an ejection assembly to remove the opened box. The present invention is concerned only with the box opening apparatus and the method of opening the collapsed box blanks.

FIGURE 1 shows a side view of the complete machine and corresponds to FIGURE 2 of the above-mentioned patent. The frame of the machine is generally designated as 10 and is rigidly formed of welded angle iron. It includes a top horizontal member 11, a transverse member 12 at the left end of the machine, legs 13 and a lower horizontal member 14 spaced in parallel relation below the top horizontal member 11. A motor 15 provides driving force for the main shaft 16 by means of a transmission 17. Shaft 16 is bearingly supported beneath the lower horizontal member 14. Motor 15 also drives a vacuum pump generally designated as 18, which supplies vacuum pressure to a pipe 20 and control valve 21 fully described in the above-cited patent. Cartons 22 are shownin a stacked position at the right hand end of the machine. The left hand end of the machine is provided with a plane surfaced member 23 secured to the top of member 12 and an angle iron 24 also secured to member 12. Boxes or cartons 22 are guided along the frame 10 by angle iron 24 and are supported upon the plane surface 23. The surface 23 is provided with an aperture through which is mounted a vacuum cup 25 which rests flush with surface 23. Cup 25 is connected to the control valve 21 by means of a pipe 26. The cup 25 is positioned so as to securely hod one side of a box 22 during opening operations when vacuum pressure is supplied to pipe 26. The foregoing description generally covers the prior structure to which the instant invention is related.

The fact that the boxes 22 are stacked in compressed form for shipping purposes provides them with an initial set or tendency to resume the collapsed position after being expanded by the opening mechanism. To counteract this tendency the following steps are proposed. First the box is expanded vertically and forced beyond the normal perpendicular angular relation of the box corners so as to overbend the corners. Then the box is allowed to resume the perpendicular relationship which is finally desired during the succeeding operations of the machine. It has been found that this method insures a stable rectangular box configuration and eliminates the loss of uniformity and clearance due to the tendency of the box to collapse.

The apparatus for carrying out these steps in the exemplary machine is shown in the accompanying drawings. A lever 28 is pivotally joined to the frame 10 by means of a shaft 34 fixed to a block 30 mounted on member 11. Lever 28 includes a pair of bar elements 31, 32 which are adjustably fastened to one another by means of bolts 33. Bolts 33 make possible the adjustment of the length of lever 28 so as accommodate various box heights. Lever 28 is fixed to a bearing collar 35 which is rotatably journalled about the shaft 34. The outer end of collar 35 has formed thereon a pinion 36. Fixed to shaft 34 adjacent the pinion 36 is a first sprocket 37.

The upper end of lever 28 rotatably has a sleeve 38 fixed to it. Sleeve 38 extends transversely above frame 10 and rotatably journals a hollow transverse tube 40. Tube 40 has a sprocket 41 fixed thereto adjacent the outside end of sleeve 38 and is coupled to flexible tubing 39, which in turn is connected to the control valve 21 by means of pipe 42. The inside end of tube 40 is connected by an elbow 43 to a short longitudinal tube 44, which is connected to a vacuum cup 45 by means of another elbow 46. A guide wheel 47 adapted to slide along the box top sides is journalled on tube 40 by means of a mounting collar 48.

The sprockets 37, 41 are drivingly connected by a chain 50. Since sprocket 37 is fixed with respect to frame 10, sprocket 41 is also fixed angularly with respect to frame 10, regardless of the angular position of lever 28. The vacuum cup 45 is therefore maintained in a horizontal position at all times.

The angular position of lever 28 is to be controlled by main shaft 16, which also times and controls all other operations of the machine. A cam 51 is fixed to the end of shaft 16 by means of a conventional mounting bracket 52. Mounted between cam 51 and a support disk 53 is a bifurcated plate 54 having legs 55 that straddle the shaft 16. Plate 54 is also guided by a roller 56 rotatably mounted on member 12. The upper end of plate 54 is provided with a rack 57 in meshing engagement with Patented Nov. 6, 1952.

pinion 36. The plate 54 also has a cam follower 58 rotatably mounted on its outer surface and adapted to rest on the periphery of cam 51. Plate 54 is biased against cam 51 by means of a chain 60 fixed at one end to the frame member 14. Chain 60 is wrapped about a sprocket mounted on a pin 61 on the back surface of plate 54 and is fixed at its remaining end to a tension spring 59 which extends downwardly to the member 14.

The cam 51 rotates in the direction shown by the arrows with a constant angular velocity. It consists of three general areas. The first is designated as 62 and is of constant radius. The second is designated as 63 and has a gradually increasing radius from 62 and then decreases in radius to form the third area-a short dip 64 which terminates as the radius of area 62.

The operation of this apparatus is very simple. The vacuum operation is unchanged from our prior patent cited above. The initial position is as shown in FIG- URE l, with no carton in operating position on member 23. While a collapsed carton 22 is being moved into position on member 23, the lever 28 is being moved in a clockwise direction due to engagement of cam area 63 by cam follower 58. The lowest position of vacuum cup 45 is shown in FIGURE 5. At this point valve 21 connects the two vacuum cups 25, 45 which grasp opposite sides of the collapsed carton 22. Then rotation of cam 51 starts to lift cup 45 and opens the carton 22. The cam area 63 decreases in radius, causing lever 28 to swing in a counterclockwise direction. Engagement of dip 64 by follower 58 causes a quick motion over the perpendicular position to the position illustrated in FIGURE 6 where lever 28 is brought to a position 30 above the horizontal. Dip 64 then quickly brings lever 28 back to the vertical position in FIGURE 1, Where it is held by cam area 62 during subsequent fiap closing operations. Finally valve 21 opens and releases the vacuum in cups 25 and 45 and the box 22 is ejected by mechanism described in our above-cited patent. The over-bending effect of this apparatus is beneficial in providing a stable box configuration of rectangular proportions, since it removes the tendency of the carton 22 to return to its collapsed position. This is of utmost importance while the box flaps are being folded and later, when the box is being loaded mechanically by high speed machines.

The apparatus described is but one form capable of carrying out the steps of this invention. Therefore, only the folowing claims are to limit and define the invention.

Having thus described our invention, we claim:

An apparatus for opening collapsed cartons in a box setting-up machine having a stationary frame, a plane surfaced member fixed to said frame in a horizontal position and feed means adapted to position collapsed cartons upon said plane surfaced member; comprising a lever pivotally mounted on said frame adjacent said plane surfaced member extending upwardly from said frame, a transverse bearing member fixed to the upper end of said lever, a support element rotatably mounted within said transverse bearing member and extending through said member and over said plane surfaced member, means fixed to said frame and operatively connected to said support element to prevent angular rotation of said element about its own axis, a pinion fixed to said lever coaxial with its pivotal connection to said frame, a rack slidably supported on said frame in mesh with said pinion, a cam follower mounted on said rack, a cam peripherally engaged by said cam follower and rotatably mounted on said frame, drive means operatively connected to said cam, said cam including a first area having a fixed radius adapted to position said lever in a vertical position, a second area of gradually increasing and then decreasing area in the direction of rotation, and a third area having a short dip of decreased radius with respect to said first area, and opposed carton grasping means on said plane surfaced member and on said support element adapted to releasably engage opposite sides of the collapsed carton.

References Cited in the file of this patent UNITED STATES PATENTS 2,217,784 Bennett et a1 Oct. 15, 1940 2,612,823 Woelfer Oct. 7, 1952 2,765,715 Kerr Oct. 9, 1956 2,780,148 Pearson et al. Feb. 5, 1957 2,782,695 Meissner et al. Feb. 26, 1957 2,863,371 Tonna Dec. 9, 1958 2,966,100 Engleson et al. Dec. 27, 1960 

